Status of research

IPP’s DEMO Studies project treats physical and technological questions that have to be clarified for preparation of a demonstration power plant.

Sketch of a tokamak demonstration power plant. From the interior to the exterior: magnet coil for induction of the plasma current (brown), main field coils (lilac), plasma vessel (green), blanket (blue), divertor (magenta), auxiliary coils (brown), cryostat (grey), shielding (grey).

Sketch of a tokamak demonstration power plant. From the interior to the exterior: magnet coil for induction of the plasma current (brown), main field coils (lilac), plasma vessel (green), blanket (blue), divertor (magenta), auxiliary coils (brown), cryostat (grey), shielding (grey).

The ITER test reactor is to show that it is possible in principle to produce energy from fusion.

To allow construction of the subsequently planned demonstration power plant, it is necessary to consider all physical and technological requirements in context and reconcile them in their respective boundary conditions.

On the physics side, challenges are presented with the cultivation of Advanced Scenario plasma discharges with high plasma density and pressure and yet with wall-sparing direction of the plasma.

On the technology side, robust wall materials, high-temperature blankets, and energy-efficient heating and current drive methods have to be developed. Accordingly, the following research topics are involved:

long-pulse or continuous operation (advanced tokamak or stellarator)

operation with high-density plasmas

plasma-wall interface: power exhaust, plasma-wall interaction

plasma diagnostics and plasma control

heating and current drive

materials for structural and functional components

in-vessel components: divertor, blanket, cooling

fuel cycle: tritium and vacuum technology

superconductor technology

remote handling and maintenance technique

efficiency, reliability and availability of all systems

Sketch of a stellarator demonstration power plant. From the interior to the exterior: support ring (grey), magnet coils (blue), plasma vessel with ports (grey), blanket (green), plasma (red). Not shown are the divertor and the cryostat, which encloses the core of the device.

Sketch of a stellarator demonstration power plant. From the interior to the exterior: support ring (grey), magnet coils (blue), plasma vessel with ports (grey), blanket (green), plasma (red). Not shown are the divertor and the cryostat, which encloses the core of the device.

IPP at Garching and Greifswald are working to solve many of these questions.

This is being done both experimentally – with the ASDEX Upgrade tokamak and subsequently with the Wendelstein 7-X stellarator as well as with experiments on plasma-wall interaction or plasma heating – and also by means of simulations and calculations in plasma theory.

The German DEMO Working Group integrates the expertness of all German fusion laboratories.